1. Field of the Invention
The present invention relates to electrical connectors, and particularly to an arrangement for preventing mismating of electrical connectors with different numbers of terminals.
2. Description of the Related Art
Electrical connector assemblies are provided in a wide variety of configurations and generally are provided in sets (i.e. pairs) of connectors, such as male and female connectors, which are used to interconnect terminating ends of electrical circuitry. The connector assemblies mount a plurality of terminals or contacts which interengage when the male and female connectors are mated. Most often, the terminals or contacts are terminated to discrete wires or to circuit traces on a printed circuit board, a combination of which must be properly interconnected. For instance, in hard wired circuitry, a xe2x80x9chotxe2x80x9d wire must be interconnected with a corresponding hot wire, a neutral wire must be interconnected with a corresponding neutral wire and a ground wire must be interconnected with a corresponding ground wire. In certain electronic applications, various signal circuitry must be properly interconnected with corresponding signal circuitry through the mating connectors. Consequently, it has been common to polarize a set or pair of mating electrical connectors so that they can be mated in only one orientation in order to properly polarize the electrical wiring or circuitry therethrough.
In order to properly understand the invention herein, the telex xe2x80x9cpolarizationxe2x80x9d is understood to define structures whereby a single set or pair of electrical connectors can be mated in only one orientation as described above, such as in only one of two 180xc2x0 orientations. The term xe2x80x9ckeyingxe2x80x9d, on the other hand, is meant to describe a system wherein one connector of any given set or pair thereof cannot be mated with another connector of another set or pair thereof, regardless of orientation.
Heretofore, there have been a variety of different polarization schemes or structures. For instance, a set or pair of electrical connectors may have keys and slots or other shapes on the outside surfaces of the connectors so that the connectors can be polarized and mated in only one of two 180xc2x0 orientations. Another scheme utilizes silos projecting from a connector housing and within which the terminals or contacts are mounted. The silos are received in receptacles of the mating connector. The silos and receptacles have a particular cross-sectional shape which allow the connectors to mate in only one of two 180xc2x0 orientations.
However, there are electrical connector systems wherein a plurality of sets or pairs of mating electrical connectors of corresponding connector assemblies are provided of similar configurations, such as generally rectangular configurations, and wherein each set of connectors mounts a different number of pairs of terminals or contacts. In such systems, although the connectors in any given set thereof are polarized in order to ensure proper mating, there is a danger that one connector of any given set will be mated with a connector of a different set, especially when outer sizes of them are substantially compatible. In other words, one set or pair of mating connectors may have only one pair of terminals or contacts. That set of connectors would interconnect two circuits. Another set of mating connectors may have two pairs of terminals for interconnecting four circuits. The sets of connectors may increase in xe2x80x9csizexe2x80x9d to include three pairs of terminals for interconnecting six circuits, four pairs of terminals for interconnecting eight circuits, and so on. In other words, the size of the connectors are determined by the number of interconnected circuits, and such connectors are manufactured, sold and/or made available in the connector industry as an identifiable xe2x80x9cSeriesxe2x80x9d or xe2x80x9cLinexe2x80x9d of electrical connectors. There is a need for providing a keying system for such electrical connector systems whereby a connector in any given set thereof cannot be mated with an opposite connector in any other set thereof having a larger number of pairs of terminals. In other words, there could be serious problems if a smaller sized connector would be connected inadvertently or erroneously to a larger sized connector.
Problems are encountered in attempting to employ keying schemes to the electrical connector assemblies described immediately above, particularly wherein the plurality of sets of connectors in the electrical connector systems employ silos and receptacles at the mating interface between the connectors in each set. These problems arise particularly in high density and/or miniaturized electrical connectors, wherein the terminals are very closely spaced in a compact array. In such circumstances, it is difficult to provide keying structures on the silos and/or in the receptacles because the walls thereof are very thin. This invention is directed to solving the problems described above by providing a unique keying system for sets of electrical connectors which use silos and receptacles at their mating interfaces. The solution provided by this invention is hereinafter referred to as an arrangement for preventing mismating.
An object, therefore, of the invention is to provide a new and improved arrangement (keying system) for an electrical connector system for preventing mismating between electrical connectors of the connector system having different numbers of terminals.
An electrical connector system in accordance with the present invention comprises a plurality of pairs of male and female connectors, the male and female connectors being exclusively engageable only with complementary female and male connectors. The mating male and female connectors comprise corresponding numbers of complementary electrical terminals for engaging with each other, an engageable latch and latch lug for securing a mating interface therebetween, and a pair of blocks cooperating with the latch to prevent mismating when a male/female connector having a different number of terminals is erroneously or inadvertently mated with the female/male connector.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.
FIG. 1 is a perspective view of a connector assembly in accordance with the present invention, with a male connector and a female connector of the connector assembly being not mated with each other;
FIG. 2 is a perspective view showing the male and female connectors of the connector assembly of FIG. 1 being in a mated condition with each other;
FIG. 3 is a view similar to FIG. 1 but showing a connector assembly having a male and a complementary female connectors, wherein the number of the terminals of each connector shown different from that of the connector assembly shown FIG. 1;
FIG. 4 is a perspective view showing the male and female connectors of the connector assembly of FIG. 3 being mated with each other;
FIG. 5 is a perspective view showing the male connector of FIG. 3 in an attempt to mate with the female connector of FIG. 1;
FIG. 6 is a side elevational view of FIG. 5;
FIG. 7 is a perspective view showing the male connector of FIG. 1 in an attempt to mate with the female connector of FIG. 3; and
FIG. 8 is a side elevational view of FIG. 7.